|Anti-cancer Foods -
The foods contain lots of antioxidants
|What we eat can hurt us, but it can also help us. According to current research studies, many of
the common foods found in grocery stores or organic markets are actually rich sources of
antioxidants. These antioxidants can benefit people at risk of certain cancers. Antioxidants
protect cells from damage caused by unstable molecules (free radicals). Radical damage may
lead to cancer development. Examples of antioxidants include beta-carotene, lycopene,
vitamins C, E, and A, and other substances.
How might antioxidants prevent cancer?
Antioxidants neutralize free radicals as the natural by-product of normal cell processes. Free
radicals are molecules with incomplete electron shells which make them more chemically
reactive than those with complete electron shells. Exposure to various environmental factors,
including tobacco smoke and radiation, can also lead to free radical formation. In humans, the
most common form of free radicals is oxygen. When an oxygen molecule (O2) becomes
electrically charged or "radicalized" it tries to steal electrons from other molecules, causing
damage to the DNA and other molecules. Over time, such damage may become irreversible
and lead to disease including cancer. Antioxidants are often described as "mopping up" free
radicals, meaning they neutralize the electrical charge and prevent the free radical from taking
electrons from other molecules.
Antioxidants are provided by a healthy diet that includes a variety of fruits and vegetables. Thus,
there isn't a single element in a particular food that does all the work. It is better to eat a variety
Which foods are rich in antioxidants?
Antioxidants are abundant in fruits and vegetables, as well as in other foods including nuts,
grains and some meats, poultry and fish. The following foods have the ability to help stave off
certain cancers and some can even help inhibit certain cancer cell growth or reduce tumor size.
Â• Beta-carotene is found in many foods that are orange in color, including sweet potatoes,
carrots, cantaloupe, squash, apricots, pumpkin, and mangos. Some green leafy vegetables
including collard greens, spinach, and kale are also rich in beta-carotene.
Â• Lutein, best known for its association with healthy eyes, is abundant in green, leafy
vegetables such as collard greens, spinach, and kale.
Â• Lycopene is a potent antioxidant found in tomatoes, watermelon, guava, papaya, apricots,
pink grapefruit, blood oranges, and other foods. Estimates suggest 85 percent of American
dietary intake of lycopene comes from tomatoes and tomato products.
Â• Selenium is a mineral, not an antioxidant nutrient. However, it is a component of antioxidant
enzymes. Plant foods like rice and wheat are the major dietary sources of selenium in most
countries. The amount of selenium in soil, which varies by region, determines the amount of
selenium in the foods grown in that soil. Animals that eat grains or plants grown in selenium-rich
soil have higher levels of selenium in their muscle. In the United States, meats and bread are
common sources of dietary selenium. Brazil nuts also contain large quantities of selenium.
Â• Vitamin A is found in three main forms: retinol (Vitamin A1), 3,4-didehydroretinol (Vitamin
A2), and 3-hydroxy-retinol (Vitamin A3). Foods rich in vitamin A include liver, sweet potatoes,
carrots, milk, egg yolks and mozzarella cheese.
Â• Vitamin C is also called ascorbic acid, and can be found in high abundance in many fruits
and vegetables and is also found in cereals, beef, poultry and fish.
Â• Vitamin E, also known as alpha-tocopherol, is found in almonds, in many oils including wheat
germ, safflower, corn and soybean oils, and also found in mangos, nuts, broccoli and other
However, five large-scale clinical trials published in the 1990s reached differing conclusions
about the effect of antioxidants on cancer. [1-5] Anyway, for balanced diet, we still should have a
variety of foods, especially vegetables and fruits.
1)Blot WJ, Li JY, Taylor PR, et al. Nutrition intervention trials in Linxian, China: supplementation with specific
vitamin/mineral combinations, cancer incidence, and disease-specific mortality in the general population. J Natl
Cancer Inst 1993;85:1483-91. 2)The Alpha-Tocopherol, Beta Carotene Cancer Prevention Study Group. The effects of
vitamin E and beta carotene on the incidence of lung cancer and other cancers in male smokers. N Engl J Med 1994;
330:1029-35. 3)Omenn GS, Goodman G, Thomquist M, et al. The beta-carotene and retinol efficacy trial (CARET) for
chemoprevention of lung cancer in high risk populations: smokers and asbestos-exposed workers. Cancer Res
1994;54(7 Suppl):2038s-43s. 4)Hennekens CH, Buring JE, Manson JE, Stampfer M, Rosner B, Cook NR, et al. Lack of
effect of long-term supplementation with beta carotene on the incidence of malignant neoplasms and cardiovascular
disease. N Engl J Med 1996;334:1145-9. 5)Lee IM, Cook NR, Manson JE. Beta-carotene supplementation and
incidence of cancer and cardiovascular disease: Women's Health Study. J Natl Cancer Inst 1999;91:2102-6. SOURCE
Antioxidants and Cancer Prevention National Cancer Institute Online Publication December 22, 2005